Help me. My phone is being navigated by someone other than me?!?

Can you send me a link or trac who or where my ID is being used? I keep getting messenger codes sent to my phone. My phone also acts like someone is on the other end going threw my phone. I’m literally watching screens bounce around from settings, to pictures, to my personal info. How the heck do I stop the hackers. And how can you help me find their location? Block them? Something.....